What happens to leftover sample after lab analysis: is the remaining sample returned, kept or destroyed?
Short answer
Some or all of a sample may be consumed during analysis, and consumed material is not returned. We keep remaining sample for 30 days; request return before the end of the retention period, at the client's cost, or it may be destroyed under laboratory procedures after that period. The English report describes supported findings for the accepted specimen, while consumed material and analysis residues are distinct from unused remaining sample.
What should I decide about the sample before analysis begins?
What is the difference between remaining sample and analysis residue?
Remaining sample is material left unused, whereas an extract, separated fraction or prepared analytical portion may no longer be the original product in its submitted condition. Analysis residues are destroyed under laboratory procedures. A return request therefore concerns available remaining sample, not the restoration of material consumed or transformed during the analysis.
When should I tell you that I want the remaining sample back?
Tell us before shipment if the sample is valuable, the only available piece, needed as a development reference or intended for examination by another laboratory. That information helps us discuss the analytical question and the proposed specimen without assuming every part can be preserved unchanged. For example, a manufacturer who wants an independent review can plan corresponding unused portions before submission instead of relying on an extracted residue as the next laboratory’s original sample.
What if I also need material for a batch comparison?
Set aside an unused reference yourself where practical, and identify the matching batch, material region and storage conditions so later findings can be compared on a corresponding basis. Our batch-comparison guide explains reference selection, while our report-difference guide explains why specimen state and analytical scope must be aligned.
How would we plan the analysis when remaining material matters to you?
1. We would review the accepted specimen and your stated need for remaining material, then discuss portions representing the target layer or batch so the question and sampling basis are clear.
2. We would choose preparation for the relevant accessible organics or elements, checking which portions need extraction, separation or other preparation and what those changes mean for the remaining original material.
3. We would investigate supported identities in prepared portions using the techniques appropriate to the accepted question, distinguishing those portions from material that has not entered preparation.
4. We would estimate supported component contributions on the stated sample basis, checking whether a separated fraction can represent the original specimen before interpreting its proportions.
5. We would review the findings against the sample question and any available reference, keeping analytical conclusions distinct from the separate request to return remaining material.
Why can analysis consume a sample or change what remains?
LC-MS/MS investigates suitable dissolved molecules and selected ion-fragment relationships, so preparation can move accessible ingredients from a film or solid into an extract that is no longer the original specimen. GC-MS investigates suitable gas-phase molecules, and separation or loss of accessible volatile material can leave a prepared portion with a different composition from the submitted product. ICP-MS measures relevant elements after preparation that breaks down suitable portions, producing elemental evidence rather than preserving those portions as usable product. The portion remaining outside those preparations and the resulting analytical residues therefore answer different physical questions, even when both originated from the same submitted sample.
What will the report describe, and what does a return request not change?
The conclusion card, component table, approximate proportions, data appendix and unresolved findings describe the accepted material and the evidence obtained from its analyzed portions. A return request does not recreate consumed material or make an altered analytical residue equivalent to an unused original specimen. Physical return and data handling are separate questions; our sample confidentiality guide explains report and data retention and confidentiality.
Our reports are research-grade analytical reports from a laboratory that is not accredited. They cannot be used for product registration or legal proceedings.
What should I declare before sending a sample whose remainder I want back?
Describe the actual product, form, photographs, SDS and analytical question, and tell us your need for remaining material before shipment; request return before the end of the retention period, at the client's cost.
Use our industrial inquiry page and shipping guide; ship after agreement, payment and an acceptance number.
Which related guides should I read?
FAQ
Can I ask for the material consumed during analysis to be returned?
Consumed material is not returned; some or all of a submitted sample may be consumed, so discuss a valuable or unique specimen before deciding what to submit.
Can another lab use an extracted residue as an unchanged original sample?
An extracted residue may have lost soluble ingredients or undergone preparation, so it should not be described as an unchanged original specimen for another laboratory’s comparison.
Does receiving my remaining sample also delete the report and records?
Returning remaining sample is distinct from deletion of information needed for the service or recordkeeping; the published confidentiality and privacy rules govern the information question separately.
Send a sample declaration and tell us what you want the specimen to answer.